Internal combustion engines (or simply engines) may be operated in a variety of environments. Some environments associated with marine applications, petroleum production, locomotive technology, mining sites, drilling sites, chemical plants, etc., may include high levels of volatile hydrocarbons. Such volatile hydrocarbons may be drawn into air intakes of the engines, be supplied to the engines' combustion chambers, and be combusted as a secondary fuel along with a regularly supplied fuel. As a result, the engines may operate at speeds in excess of a prescribed design limit and become uncontrollable. Such conditions are commonly termed as a runaway condition. Engine damage may occur unless the secondary fuel source is prevented from being induced into the engines. To prevent a runaway condition, an engine generally includes one or more air-intake shutoff valves. Air-intake shutoff valves typically include a gate that facilitates either a blockage or an allowance of an airflow to the engine. In the event of a runaway condition, this gate is actuated to a closed position to starve the engine of oxygen and the secondary fuel source, and thereby terminating combustion in the cylinders and preventing the engine from incurring damage.
During a gate closure, an airflow may possess a generally high volume and velocity. Therefore, as the gate transitions from an open position to the closed position, a resulting pressure differential across the air-intake shutoff valve may exert a relatively significant force on the gate, restricting the gate from full closure. On several occasions, the air-intake shutoff valve sustains a delayed closure or remains at least partially open. In such an event, an airflow may continue to be induced into the engines, deterring an engine shutdown. An incomplete closure may also refrain other interconnected air-intake shutoff valves from effectively closing associated air intake passages. Additionally, a natural frequency of the air-intake shutoff valve operations may interfere with the engines' natural firing order, leading to premature wear of the air-intake shutoff valves.
U.S. Pat. No. 4,537,386 ('386 reference) relates to an engine shutdown valve applied to an engine induction manifold to regulate induction of air into an engine. The '386 reference discloses a movement mechanism of the engine shutdown valve between an open position and a closed position by use of a gate actuating spring. Although a spring force of the gate actuating spring may be sufficient to facilitate closing of the engine shutdown valve, a full closure of the engine shutdown valve, in presence of a laterally acting airflow, may remain arduous.